"Because they treat bodies that are still growing, targeted drugs mean better quality of life and fewer side-effects for our nation's youngest cancer patients," the organization said.

Cancer in children is rare, but it is the leading cause of death by disease past infancy among children in the United States. In 2014, it is estimated that 15,780 children and adolescents ages 0 to 19 years will be diagnosed with cancer and 1,960 will die of the disease in the U.S., according to the National Cancer Institute, which is part of the U.S. Department of Health and Human Services.

The most common types of cancer in children and adolescents are leukemia, brain and central nervous system tumors, lymphoma, rhabdomyosarcoma, neuroblastoma, Wilms tumor, bone cancer, and gonadal (testicular and ovarian) germ cell tumors, the National Cancer Institute said.

As of Jan. 1, 2010, that agency said, the U.S. had about 380,000 survivors of childhood and adolescent cancer.

Research and treatment appear to have helped. The National Cancer Institute said the outlook for children with cancer has improved since 1975, when slightly more than 50 percent of children diagnosed with cancer before age 20 survived at least five years. That rate jumped to 80 percent from 2004 to 2010, the agency said.